The disclosure herein describes a visor attachment for use in combination with a conventional safty helmet wherein the visor is pivotally mounted at the back of the helmet; when used, such helmet is thus worn front-to-back. The attachment body has two side extensions which are adapted to fit into rim...http://www.google.fr/patents/US5012528?utm_source=gb-gplus-shareBrevet US5012528 - Visor attachment for safety helmet
